用于雷达接收机的开关电源的低纹波设计

介绍了某机载雷达接收机电源的实施方案.该方案采用开关电源代替线性电源,通过减少开关电源的输出纹波和干扰,满足接收机对电源的纹波要求.该方案提高了接收机电源的效率,减少了接收机电源的体积和重量,优化了接收机系统的设计.文中主要描述了接收机系统中所采用的开关电源的组成、各部分的作用、关键技术及解决途径.     

某型无人机电源滤波系统的设计

针对无人机电源系统对输出电压纹波和噪声的特性要求,设计了以两级LC滤波器为核心的正激电源滤波系统。仿真和实验结果表明,系统输出电压稳定、噪声低、纹波小。该电源系统已投入无人机航磁探测野外实验中,运行可靠、效果良好。     

宽输入范围无人机稳压电源的设计

介绍了一款宽输入范围的无人机机载开关电源的设计方法, 采用了基于LTC3777控制芯片的四开关同步整流非隔离的升、降压变换技术,为后级变换器提供稳定供电,保证了后级变换器的优化设计,提高了无人机整体电源效率;分析了该种控制芯片的控制原理和电源主要元器件的设计方法。实验结果表明:采用文中提出的变换器作为前级预稳的两级式变换器,可以满足无人机对电源高效率、高功率密度以及宽输入范围的要求。     

锂电池供电的高效、低纹波、低高频噪声电源设计

设计了一种锂电池供电的非隔离多路直流电源,嵌入到便携式移动设备中,电源有两路功率较大,效率、纹波、高频噪声的要求高。存在锂电池输出电压低时与电源输出电压较接近,普通的降压DC/DC难以实现的问题,设计采用了超低压差、占空比可达100%、高效率的BUCK变换器,解决了该问题。其中一路要求输出电压大范围可调、纹波小于1m V;设计采用了BUCK加LDO电路进行稳压,又明显减小了电源纹波;还用减法放大器控制BUCK电路,保持LDO的工作压差是较小的固定值,保证了电源的高效率。电源又增加了LC滤波和磁珠滤波,对进一步减小纹波和高频噪声的效果较好。     

Zeta型电子束焊机高压稳定电源的纹波抑制与稳压

在传统的电子束焊机电源系统中,由于开关电源自身的原因,存在较高的固有高纹波输出电压特点,导致电子束焊机电源系统的输出电压不稳定。为此,采用耦合电感技术,设计了一种Zeta型变换器为主电路的电子束焊机的电源系统,其原理是将耦合电感技术与Zeta型变换器相结合,合理分配Zeta变换器中的两耦合电感的耦合程度来抑制纹波。同时,采用PI控制-前馈控制构成的复合控制器提高电源系统的控制精度和输出稳定精度。PLECS软件仿真结果表明,该系统不仅抑制输出电压纹波效果十分明显,而且还具备输出电压稳压精度高、动态特性好和工作可靠等特点,验证了理论推导的正确性。     

数字式多相脉宽调制电源

20世纪90年代以来，随着芯片工作电压的降低和工作电流的增大，市场对直流电源模块的需要一直在增长，它们被广泛用来驱动微处理器和专用集成电路或模块。由于电路的工作电流不断增大，电源由5V转为12V。一般情况下用多相降压变换器来降低电压的纹波，调整12V电源。用户对电源的性能要求，如软启动、供电连续性、动态特性等越来越高，使电源规格越来越复杂。为了满足新的市场要求，模拟多相控制集成电路应运而生。     

用于GPS接收机的130 nm PD-SOI低噪声放大器

基于130 nm PD-SOI工艺,设计了一种用于GPS接收机射频前端的单片低噪声放大器(LNA)。利用SOI工艺特有的低噪声特性,降低了衬底耦合到电路的噪声。采用单独的带隙基准源和LDO为低噪声放大器供电,降低了电源纹波和高频噪声对放大器噪声性能的影响。测试结果表明,在3.3 V电源电压、1.575 GHz工作频率下,该LNA的噪声系数仅为1.49 dB,增益为13.7 dB,输入回波损耗S11、输出回波损耗S22均小于-15 dB,输入P1 dB为-13 dBm,IIP3为-0.34 dBm。     

一种用于GPS接收机的低噪声放大器

针对GPS接收机低功耗、低噪声、高增益的要求,采用功率限制下噪声匹配技术、阻抗匹配技术和电源复用技术,设计了一款可应用于GPS接收机的单端输入差分输出低噪声放大器,减少了巴伦损耗。采用SMIC 0.13 SymbolmAm CMOS RF工艺和全定制集成电路设计方法,工作频率为1575 GHz,对电路进行版图后仿真。仿真结果表明,该低噪声放大器在1.2 V电源电压下,功耗为4.8 mW,增益为22.65 dB,噪声系数为1.388 dB。     

电源纹波对频率源频谱纯度的影响

在微波测试领域,关于电源纹波基本是原理性研究,而针对性研究电源纹波对频率源相位噪声影响的分析或者实验实例更少,对微波电路的电磁兼容设计方面缺乏参考。文中在电源纹波对频谱纯度的影响概念性分析基础上,主要针对现代雷达系统中电源纹波对频率源频谱纯度的影响展开研究,通过分析电源纹波对频谱纯度影响的机理,采用模拟数据仿真的方法探索电源纹波对不同类型频率源频谱纯度的影响,并进行实际测试数据对比仿真结论,得出频率源频谱纯度受电源纹波影响的主要因素以及相互关系,为电路设计者提供数据支持。     

低噪声雷达激励器和接收机在机载中的应用

本文叙述了应用于Ｓ波段相干脉冲多普勒机载雷达中的低噪声激励器和双超差接收机的设计性能，展示了最先进雷达的相位噪声和检测特性。雷达激励器由双本屏提供多路稳定度高，相干性好，高频谱纯度和低相位噪声的信号输出。     

Four-quadratic DC magnet power supply with fast dynamic responseand low ripple content

The authors discuss a power supply configuration based on a switching converter, with reasonably fast dynamic response and low ripple content, so that the linear power supplies can be replaced in four-quadrant DC magnet power supply applications. A new power supply configuration, based on the combination of a frequency converter and a dual converter with circulating current, is proposed for application in four-quadrant DC magnet power supplies. The dual converter is used with circulating current mode for smooth transition of output current polarity. The frequency converter is used at the front of the dual converter to boost the AC line frequency so that the dynamic response can be improved without increasing the ripple content     

A low noise,high power efficiency supply regulator for near-field power delivery

In order to deliver near-field electromagnetic power to a biomedical device or an RFID tag efficiently, the downlink signal is preferred to be at a high voltage level. To reduce power consumption and meet low supply requirements, it is advantageous for the remote device power supply to step-down the input voltage following rectification, typically using switch-mode regulators. The output ripple of a switched capacitor converter is inversely proportional to the filtering capacitance at the output node and switching frequency. In this paper, a hybrid DC–DC converter utilizing a switched capacitor regulator in master–slave configuration with a linear regulator is presented. Linear regulator actively cancels the switching ripple, while low frequency and DC current is provided by the switched capacitor converter. The converter is designed to receive an average input voltage of 5 Vpk from the receiver coil, with an output voltage of 2 V, and 5 mA of output current. The proposed regulator is fabricated in 0.35 μm technology. The power efficiency is measured to be 67%, with a nominal peak to peak ripple of less than 2 mV at the output.     

一种基于CUK变换器的通用型固体激光电源

介绍了一种性能优异的新型固体激光电源。采用新型的变换器结构,使电源具有较强的通用性。给出了原理电路模型,分析了工作原理。实验证明,该电源结构简单、适应范围广、成本较为低廉、工作可靠。     

用LMS算法消除开关噪声对射频接收机的影响

针对DC-DC开关电源在为射频接收机供电时,引入过大的电源纹波噪声干扰问题,提出用LMS算法从基带消除纹波噪声干扰的解决方案。从纹波噪声建模出发,根据ZigBee标准利用Simulink仿真工具,搭建了带电源纹波噪声干扰的射频接收机仿真模型,并利用两级LMS算法调整的自适应滤波器,从基带消除纹波噪声干扰。仿真结果显示,在100 mV以下的纹波电压情况下,带LMS算法噪声消除的射频接收机系统仍能正常工作;超过100 mV后,算法能减小纹波噪声对射频接收机的干扰。     

Analysis and design of an LCL-T resonant converter as a constant-current power supply

An LCL-T resonant converter (LCL-T RC) is shown to behave as a current source when operated at resonant frequency. A detailed analysis of the LCL-T RC for this property is presented. Closed-form expressions for converter gain, component stresses, and the condition for converter design optimized for minimum size of resonant network is derived. A design procedure is illustrated with a prototype 200-W 20-A current-source power supply and experimental results are presented. The LCL-T RC as a current source offers many advantages such as easy parallel operation and low circulating currents at light load. Additionally, with appropriate phase shift in paralleled modules, the peak-peak ripple in output current is reduced and the ripple frequency is increased, reducing filtering requirements. The leakage inductance of a transformer can be advantageously integrated into the resonant network. These merits make the topology applicable in various applications such as magnet power supply, capacitor charging power supply, laser diode drivers, etc.     

A New Approach to Reducing Output Ripple in Switched-Capacitor-Based Step-Down DC–DC Converters

Rapidly dropping power supply voltages and tight voltage regulation requirements for integrated circuits challenges power supply designers. A novel interleaved discharging (ID) approach is presented to reduce the output ripple in step-down switched-capacitor (SC) dc-dc converters. Simulation and experimental results of a four-stage SC dc-dc converter show that the ID approach can reduce the output ripple by a factor of three. The proposed approach also improves the converter efficiency by 7%. The ID method provides flexibility in the design optimization of step-down SC dc-dc converters     

DCVM模式下的高功率因数Cuk变换器的研究

首先介绍了不连续电容电压模式（DCVM模式）下的Cuk电路的运行特征,分析了该模式下Cuk电路的3种工作状态。因DCVM模式的Cuk变换器的平均输入电流波形自动地跟踪了输入电压的波形,从而使变换器的功率因数大大提高,达到了功率因数校正的目的,并依此提出了对该电路设计所需的一些参数计算方案。     

Buck or boost tracking power converter

A cascade of buck and boost converter is presented here. The control operates in a manner that the converter is either in buck or boost (BOB) mode on a cycle by cycle basis. It transitions between the modes seamlessly to provide a tracking power conversion function for modulating the power supply of a variable envelope radio frequency (RF) power amplifier. The control algorithm and its implementation using switched capacitor circuits is described. Simulation and measured experimental results including converter efficiency, tracking accuracy, and spectrum at the output of the RF power amplifier are provided. This control technique allows seamless transition between the buck and boost modes while tracking RF envelopes with bandwidth greater than 100 kHz, and maintaining extreme accuracy and extremely low ripple. The efficiency of this converter operating at 1.68 MHz is close to 90% over a wide range of conversion ratios. The area of the power converter is extremely small allowing this to be integrated into a cellular telephone. The controller was integrated as part of a larger power management IC as well as a discrete IC.     

开关电源纹波对射频收发系统性能影响

研究了使用开关电源为射频系统供电时,射频系统对于电源纹波的容忍度。从电源纹波泄漏到基带信号、电源纹波与射频信号混频两方面研究了电源纹波对系统的影响,并根据协议规范,确定出电源纹波值。在IEEE 802.11g协议下,通过仿真得出电源纹波应控制在15 mV以下。